Hitherto, olefin-based polymers obtained by graft-modifying a polyolefin such as polyethylene and polypropylene with an unsaturated carboxylic acid or an acid anhydride thereof have been used as modifiers for various resins or tackifiers.
Meanwhile, it has been expected that a blend of low-stereoregular polybuten-1 produced in the presence of metallocene-based catalysts with polypropylene produced in the presence of magnesium-titanium-based catalysts, is usable to control an elastic modulus of the polymer, or form a heat-seal layer in multilayer films, etc. However, the polybuten-1 has been further required to show much higher strength and adhesiveness.
Under these circumstances, an object of the present invention is to provide a modifier that is useful for imparting a high adhesiveness, a high strength and a good softness to polyolefins, and for obtaining sealants having a high adhesiveness, or polyolefins having an improved compatibility to inorganic fillers, etc., as well as an adhesive composition containing the modifier.